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Anyone good at maths? (probability)

Stuck with some basic maths probabilty.....

Heres my question guys:
[b]a component is made in 3 stages. the first stage involves building from one of four machines A,B,C and D all with equal probabilites. Second stage is trimmed using one machine either E,F or G, and finally polished using either machine H or J and it is twice as likely to be the former as H works faster[b]

Determine the porbabilty of:1. a component is polished on machine H is it 2:1?

2. it is trimmed on either machine F or G2/3 or 66%

[b]3. a component is formed on either machine A or B, trimmed on F and polished on H]/b]i have no idea

now its late, I am drunk and have no paper, still, I think its like this:

1. is 2/3
2. is 2/3
3. is 1/9
4. is 1/12
5. is 1/6
6. is 1/12

Basically you set probabilty to each event on each stage separately.
You have 3 stages and you always multiply in between. (if the probability of getting through certain stage is 1/4 and through another stage is 1/3, then MP it will give you 1/12)
However when its "OR" on certain stage, you add the probabilities for all events "OR" includes.
And when certain stage is left out the probabilty is of course 1, since it has to go via that stage anyway.

Originally posted by F_A_L_C_O_N now its late, I am drunk and have no paper, still, I think its like this:

1. is 2/3
2. is 2/3
3. is 1/9
4. is 1/12
5. is 1/6
6. is 1/12

Basically you set probabilty to each event on each stage separately.
You have 3 stages and you always multiply in between. (if the probability of getting through certain stage is 1/4 and through another stage is 1/3, then MP it will give you 1/12)
However when its "OR" on certain stage, you add the probabilities for all events "OR" includes.
And when certain stage is left out the probabilty is of course 1, since it has to go via that stage anyway.

hope that makes some sense

Thanks falcon, i have drawn a tree chart now and see how you have done it.
makes great sense now, thanks mate.